Biology / Unit 6 Bio 1305 short lesson, about 20 seconds
"A DNA Mutation Is Always Harmful"
Captions available
The idea
A DNA mutation's effect ranges from harmful through neutral to occasionally beneficial, since silent mutations change nothing and many missense changes barely affect function.
In practice
A silent mutation leaves a protein's sequence unchanged, while a rare beneficial mutation can improve its function.
Where people slip
Mutations are raw material evolution acts on precisely because their effects vary — treating every mutation as harmful ignores this range.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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